The removal of phenolic compounds from water streams is of great importance due to their high toxicity, carcinogenicity, and bioaccumulation in food chains. In this study, the separation of four ...representative phenolic compounds (including phenol (PhOH), p-cresol (MePhOH), p-chlorophenol (ClPhOH), and p-nitrophenol (O2NPhOH)) from aqueous solutions by pervaporation using poly(ether-b-amide) (PEBA) membrane was studied. The effects of feed concentration (up to 0.6 wt%) and operating temperature (30–70 °C) on the separation performance were investigated. While the permeation fluxes of phenolic compounds increased at higher feed concentrations, the increase in the flux was less than proportional, leading to a decrease in the enrichment factor. It was also shown that both the permeation flux and the enrichment factor increased with an increase in temperature. However, the permeabilities of the phenolic compounds in the membrane were impacted differently. Of particular interest were the coupling effects of co-existing phenolic compounds due to permeant-permeant interactions, which were found to be significant in permeation of multiple phenolic compounds that were relevant to practical applications. The permeation of PhOH, MePhOH and ClPhOH was all affected adversely by the presence of additional phenolic compounds in the feed solution, while the opposite was true for the permeation of slow-permeating O2NPhOH. Depending on the specific phenol solute, high-purity phenol crystals could be produced from the phenol-enriched permeate via de-sublimation in the cold trap, which was of particular interest for practical applications.
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•Effective removal of phenolic contaminants from water was demonstrated.•Strong coupling effects in pervaporative removal of multiple phenolic compounds.•Phenol crystals may be obtained from phenol-enriched permeate via de-sublimation.
To improve understanding of the potential benefits of quinoa as a staple food, the chemical composition, bioactive compounds, and total antioxidant capacity of six different colored quinoa cultivars ...were studied. The findings revealed that yellow quinoa exhibited a higher protein content, while white and red quinoa seeds contained greater amounts of starch, and black quinoa seeds were richer in fiber. A total of 20 phenolic compounds were identified, encompassing 13 phenolic acid variants and 7 flavonoid variants. The levels of phenolic acids (131.96–223.28 μg/g) and flavonoids (91.86–131.14 μg/g) exhibited variations based on seed color, with crimson and yellow quinoa seeds demonstrating the highest concentrations of both phenolic acids and flavonoids. Notably, crimson quinoa seeds displayed the highest content of betalains (36.17 μg/g). Saponin content was highest in yellow (178.82 mg/100 g), while the lowest in black (106.5 mg/100 g). Furthermore, it was observed that the phenolic acids present in red quinoa seeds exhibited the most potent DPPH free radical-scavenging ability. Conversely, black quinoa seeds displayed the highest iron-reducing antioxidant activity and ABTS free radical scavenging ability among all the samples examined. Moreover, black quinoa seeds demonstrated the highest overall antioxidant activity compared to other quinoa varieties This study suggests that colored quinoa seeds are rich in phenolic and betalains compounds with antioxidant capacity. The correlation analysis indicated a significant positive relationship between antioxidant activity and phenolic compounds up to a certain degree. As a result, colored quinoa can serve as an antioxidant food.
•Six differently colored quinoa seeds varied in their contents of phenolic compounds.•There were significant differences in antioxidant activities between seeds of different colors.•There was a discernible positive correlation between antioxidant activity and phenolic compounds to a certain degree.•Differently colored quinoa seeds can improve food security and provide health benefits.
Xanthine oxidase (XOD) catalyses the oxidation of hypoxanthine and xanthine to uric acid, and inhibition of its activity has become the main strategy to reduce uric acid production. Honeysuckle (HON) ...which is rich in polyphenols potentially has the capacity to inhibit XOD activity. However, it carries the bitter and astringent flavor as well as many traditional Chinese medicines, along with that most of the polyphenols in HON exist in bound form, the exploitation and application of HON in food is limited. In this study, we investigated the effects of Lacticaseibacillus rhamnosus L08 fermentation on the bioactive components, XOD inhibitory activity and flavour characteristics of HON. The results showed that the XOD inhibitory activity was increased by 2.08 times after 96 h of fermentation. It was demonstrated that the increase in the total flavonoid content and total phenol content was the main reason for the enhancement of the fermentation solution's XOD inhibitory activity and antioxidant activity. Moreover, the fermentation also enriched the composition of volatile components of HON and reduced levels of undesirable flavour substances, which made the usage of fermented HON as functional food or in pharmaceutical use feasible and applicable.
•Honeysuckle had milti-functional properties including lowering uric acid.•LAB fermentation was proved to increase the phenol and flavonoid contents.•L. rhamousus L08 improved the bioactivity and bioaccessibility of honeysuckle.•Fermentation also improved honeysuckle flavor profile.
•Composition and nutritional value of lettuce were reviewed.•Nutritional value significantly varied with lettuce types and leaf color.•Lettuce is a good source of several minerals and fiber.•Lettuce ...contains bioactive compounds such as folate, β-carotene, lutein, and phenolics.
Lettuce is one of the most widely consumed vegetables worldwide, but its nutritional value has been underestimated. Lettuce is low in calories, fat and sodium. It is a good source of fiber, iron, folate, and vitamin C. Lettuce is also a good source of various other health-beneficial bioactive compounds. In vitro and in vivo studies have shown anti-inflammatory, cholesterol-lowering, and anti-diabetic activities attributed to the bioactive compounds in lettuce. However, nutrient composition and bioactive compounds vary among lettuce types. Crisphead lettuce, the most popular type of lettuce in the US, is comparatively low in minerals, vitamins, and bioactive compounds. More nutritious lettuces are leaf type lettuce and romaine with folate content comparable to other rich leafy vegetable sources. Red pigmented lettuce contains higher phenolic compounds than green lettuce. Due to increasing popularity, the nutrient contents in baby lettuce were also examined. Baby green romaine was especially high in vitamin C. In this review composition and nutritional value of different lettuce types were summarized, which can help growers and consumers choose lettuce types with higher nutritional benefits.
The profitability and sustainability of future biorefineries are dependent on efficient feedstock use. Therefore, it is essential to valorize lignin when using wood. We have developed an integrated ...biorefinery that converts 78 weight % (wt %) of birch into xylochemicals. Reductive catalytic fractionation of the wood produces a carbohydrate pulp amenable to bioethanol production and a lignin oil. After extraction of the lignin oil, the crude, unseparated mixture of phenolic monomers is catalytically funneled into 20 wt % of phenol and 9 wt % of propylene (on the basis of lignin weight) by gas-phase hydroprocessing and dealkylation; the residual phenolic oligomers (30 wt %) are used in printing ink as replacements for controversial
-nonylphenol. A techno-economic analysis predicts an economically competitive production process, and a life-cycle assessment estimates a lower carbon dioxide footprint relative to that of fossil-based production.
•Grape productivity from the OP and CP systems were equivalent.•A greater number of volatile compounds were found in grape juices from OP than in CP juices.•Total phenolic compounds and anthocyanins ...from OP and CP juices were not different.•Fifty-six percent of tasters preferred OP juices.
The similarities and differences between foods produced under organic (OP) and conventional (CP) systems remain a controversial topic. In order to contribute to the evolution of this theme, grapes and juices were produced from vineyards in OP (n = 20) and CP (n = 20). All juices were elaborated using the same processing technology. Grape productivity was evaluated, and the classic characterization of juices was performed, followed by an in-depth characterization of mineral composition, pesticide residues, volatile compounds, phenolic compounds, and anthocyanins, as well as sensory analysis. In total, 101 dependent variables were monitored. From this set of variables, it was observed that grape productivity and the overall classic composition of juices from OP and CP systems are equivalent. Similarly, the mineral composition was equivalent, exception of the presence of a high concentration of Al in only one juice from the CP. As expected, pesticide occurrence was more frequent in CP juices (14/20), however, in all cases at much lower levels (1600 times lower or more) than the limits allowed by regulations. Residue occurrence also occurred in OP juices (2/20), which are not allowed by current regulations. In terms of volatile compounds profiles, 40 compounds were identified and quantified in OP juices, and 34 in CP juices. Regarding total phenolic compounds and total anthocyanins, the juices were equivalent. OP juices had a higher sensory preference. In conclusion, among101 variables evaluated, 75 indicate that the juices are equivalent. The 26 variables leading to technical differences are related to: 1) a higher frequency of residues in CP juices compared to OP juices; 2) a greater diversity of volatile compounds in OP juices; 3) differences in minor phenolic compounds and anthocyanins; and, 4) preference for OP juices.
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•The first study of microwave-assisted extraction of phenolics from multiple single food wastes and their mixtures.•Physical and composition characteristics impact on dielectric properties, heating ...profiles, and processing times.•Identification of features affecting target phenolic extraction yield from single and mixed waste streams.•Illustration of higher extractant concentrations in mixed waste than a simple addition model.•Degradation kinetics of target phenolics.
Microwave-assisted extraction (MAE) of natural antioxidants from food waste (FW) offers an economically appealing waste management strategy. However, MAE from mixed FW has received limited attention. We characterize five single waste streams (apple, coffee, olive, tomato, and potato peel waste) and study MAE of phenolic acids from select feedstocks and mixtures. This library of materials enables us to unravel the relationship of FW composition and physical properties with dielectric properties, heating, and extractive yields. Protein, ash, and moisture contents affect dielectric properties the most. Our study unveils the significance of moisture in free (> 20 wt%) and bound states (< 20 wt%) on FW dielectric properties, heating, and target acid yields (at least 33 % enhancement). Microwaves primarily heat the solvent (dimethylformamide) due to its superior dielectric properties compared to FW (dry and moist, single and mixtures) at ≤ 0.05 solid-to-liquid ratio (g/mL). High moisture content (> 20 wt%) provides higher phenolic yields at lower temperatures (< 100 °C) and shorter times (≤ 10 min) due to enhanced heat and mass transfer by microwaves. Further, our data indicates significant interactions between mixed FW components that drive 2–3x higher yields than those predicted from a simple additive model from single component results. Our work provides new insights for developing versatile MAE strategies to treat mixed FW feedstocks.
Our work provides new insights into developing versatile microwave-assisted extraction strategies to treat complex mixed food waste feedstocks. Display omitted
Wastewater deriving from cellulose and paper manufacturing is one of the most important industrial effluents due to its large-volume production and high pollution load. Effluent deriving from the ...pulp bleaching stage (Kraft E1 effluent) remains one of the major issues faced by paper mills among all wastewaters generated in each stage of paper-making processes. Kraft E1 effluent was submitted to a sequential chemical (ozonization) - biological (immobilized laccase) treatment. Laccase was obtained from Trametes versicolour in liquid medium of culture using 2,5 -xylidine as inducer. Crude laccase extract was immobilized through covalent binding in Montmorillonite KSF and Eupergit
®
C supports based on different protocols. Eupergit
®
C has shown the best protein immobilization (51%), retention activity (100%), and operational stability (ten oxidative cycles) results. Enzymatic treatments using free and immobilized laccase onto Eupergit
®
C were applied to Kraft E1 effluent. After 18-h treatment, total phenol removal reached 20% and 40% in free and immobilized laccase, respectively. Ozone combined to enzymatic processes using reactor assembled with immobilized laccase (31 U g
−1
, total mass = 10.0 g) had effect on decolonization efficiency and on total phenols' removal from Kraft effluent. Ozone treatment was capable of removing 52% of total phenols and 76% of colour from the investigated effluent. Sequential enzymatic treatment has increased total phenols' removal to 64% within 30-minute treatment and reached 70% removal within 60 minutes. The herein observed additional phenol removal based on enzymatic treatment is an important outcome if one takes into consideration the fraction of total phenols that could not be removed by the ozone process.
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